@lando242: Oh yes, it is very egoistic reporting bugs/ difficulties. Not that Opera could use those information to improve their products. That's very egoistic, isn't it?

@vux777, @sgunhouse:
Neither opera://flags/#site-tiles (it is disabled, still by default) nor disabling plugins solved the problem.
But I think I found a solution:

The entries in the 'Recommended' bar (@herrevo's screenshot), really seem to come from Speed Dial. But at least for me they didn't appear on the Speed Dial page (blank new tab). Maybe it was some kind of a bug? How ever I found a work around:

I linked Opera on Android with the one running on my pc using synchronization.

I opened a new blank tab in Opera on Android, that made Speed Dial (for me it's called 'Schnellwahl') appear.

Address bar recommendations:
This feature is now enabled by default. To enable or disable the feature, please go to Settings and in the “User interface” section, modify the “Show extra suggestions” check-box setting.